Thursday, December 12, 2013

There is something about construction equipment. It's big. It's loud. It wrecks stuff and it makes stuff. What's not to love?

As a kid I fell into the tank/airplane as opposed to trucks and trains camp of toys. As an adult (or at least as a man child) I've developed an appreciation for heavy equipment of all types: cranes, bulldozers and yes... the ubiquitous dump truck.

I never had a toy dump truck but I've now built two of them. The first one was for a kid who was named Aaron (actually, I think his name is still Aaron.) I built it as a total one off about six or seven years ago. Some Oak, some Aspen and a few dowels. I heard back that the frazzled mom got several hour of much needed relief as Aaron loaded and dumped and reloaded crayons with it in the other room. So, mission accomplished.

The little driver had a peg that went down through the chassis and would bounce up and down as the truck was pushed thanks to a cam on the front axle. (Note that the driver is a rather handsome devil...)

While that was a fun little "action" piece to include, it was a bit fiddly and my guess it that it won't hold up to the day to day pounding a toy like this will take.

Okay... so much for the past. Here is the present. I had been asked a while ago to build a toy truck for a two year old boy. (Truth be told, he was only one when the request came in... just saying.) I wanted it to be sturdy, made from things on hand and easy to reproduce. Also, not just a truck, but one that did something - that had something that moved besides the wheels. The obvious answer - another dump truck.

The chassis and cab were cut from a standard 2x4. I started with a piece about 10" long and trimmed it up to be 2 1/2" wide long x 1 1/2" tall. I cut a piece 7 1/4" to be the chassis and then used the remaining piece for the cab. I cut a curve for the front of the cab to give it a toy look. I then drilled a pilot hole all the way through to help me line up a 3/4" Forstner bit (named, by the way, after its inventor - Benjamin Forstner) to make the window.

Axle holes were drilled in 2" from each side and 3/8" from the bottom. I used a 7/32 drill bit for these holes. Since I'm using axel pegs and not a full length dowel, I only drilled the holes deep enough for those. If I wanted to save some time (and chassis had been perfectly square) drilling straight through would have been fine. The cab was glued and clamped flush with the front of the chassis. There are also shallow holes around the front to house the headlights and holes in the back that will be used to pivot the bed.

The bed of the truck (you know... the dumpy part of the dump truck) was made from 3/8" wine crate wood. This particular wine crate was from Chile. I marked out and cut the sides of the bed so that a small tab would be at the back of the bed for me to make a hinge.

Again, I was using pegs so the holes in the bed side are 1/4" to allow free movement around the pegs but the holes behind it in the chassis are 7/32 to allow a tight fit.

The bottom part of the bed was the same width as the chassis of the truck. You can see from this photo how the front of the bed rests on top of the bottom part but the bottom part is sandwiched between the sides. The chassis sides were sanded on the belt sander and that little bit of extra clearance allowed the bed to move freely without the bed sides "pinching" the chassis sides.

One last note on the bed is that the gate/flap on the back doesn't rest on the floor but butts up against it and uses it as a "stop." The flap isn't installed here but this shows the gap where it will fit in. This photo also shows where I marked an area of the chassis to be cut off and rounded over to allow the bed to move freely when dumping cargo.

The flap needs to be just slightly smaller than the opening at the back of the bed to allow it to swing freely. I drilled 1/8" holes in the flap and slightly larger ones in the sides of the bed. I then inserted pieces of 1/8" dowel from either side into the flap and this formed a hinge. I flush cut the dowels to match the bed sides and now the gate opens as the bed is lifted. This shows the completed assembly from above on the finished toy.

So here are all the parts cut out, sanded and glued (note that the flap wasn't attached at this point..)

And here is everything after several coats of Danish Oil* and the wheels, headlights and flap attached.

Final assembly was just putting the pegs through the bed sides and gluing them into the holes in the rear of the chassis. I use a 1/32" scrap as a spacer whenever I'm attaching wheels or pegs to be sure I don't drive the peg in so far as to turn it into a nail and bind the parts.

All in all, it was a really easy, satisfying build. The little boy who got this truck seemed very happy with it and so far it has stood up to some drops and overnights in his bed.

So here is "Dumpy" (as he was named by the little boy) in action.

(* Please Note: No Danes were injured in making of this toy but one Irish/Sicilian American may have gotten a splinter or two.)﻿